The present invention relates to a vehicle clutch assembly, particularly for agricultural or industrial tractors.
In a known manner, standard tractor clutch assemblies normally comprise a first and a second disk clutch, the first disk clutch being interposed between the tractor motor drive shaft and the transmission, and the second disk clutch being interposed between said motor drive shaft and an output shaft defining the power take-off (PTO) for providing rotational power to eventual implements carried or pulled by the tractor.
In most cases, the two clutches are arranged side by side, and are normally maintained in the closed or engaged position by a common elastic element interposed between the end disks of the two clutches. The first clutch is normally opened or released using the clutch pedal, while the second clutch, which is used less frequently than the first, is normally opened or released and maintained in the released position by means of a hand-operated lever connected by a Bowden cable to a lever device controlling the second clutch and presenting a number of rigid connecting members for exerting a force in a direction opposite to that exerted by the elastic element.
Though widely used, known clutch assemblies of the above type may be the cause of injury to the tractor operator or any bystanders in the vicinity of the tractor when the second clutch is maintained in the released position by the lever. In this condition, in fact, in the event of accidental breakage of any of said connecting members or the Bowden cable, the second clutch is immediately brought in the engaged position under influence of the elastic element between the two clutches, thus inadvertently and unintentionally activating the power take-off and the eventual implement connected to it.